Standardize settings structure

[milanXpetrovic]

Description

The current settings folder contains a main_settings file and several step-specific settings files. However, the naming conventions are inconsistent across these files, leading to confusion and mistakes during development. Some settings are also unused and need to be removed.
Additionally, all filesystem paths should be handled using the pathlib.Path library instead of raw strings to improve reliability, readability, and portability.

Issues identified

• Inconsistent naming conventions across settings files.
• Unused settings variables that should be removed.
• Some settings exist in multiple files but use different names.
• Paths are defined as strings instead of using Path.
• Overall structure of the settings folder lacks clarity.

Tasks

• Audit all settings files and list unused or duplicate fields.
• Standardize naming conventions across all settings modules (e.g., snake_case, consistent prefixes).
• Unify shared settings into a single location or ensure correct import structure.
• Replace all path strings with Path(...) objects.
• Clean up folder layout if needed (e.g., settings/main.py, settings/video.py, etc.).
• Update documentation to reflect the new structure.

Expected behavior

Settings are clean, consistent, and easy to maintain. Paths use Path instead of raw strings. No unused or duplicated configuration fields remain.